Question

The model represents an equation. What value of x makes the equation true?

A) 29/8

B) 29/2

C) − 29/2

D) − 29/8

Answer 1

A) 29/8

Explanation:

Identify the blocks. As you can see there are 5 x blocks on the left, and 9 -1 blocks on the left. On the right there are 3 -x blocks and 20 1 blocks. With this, form the equation.

5x - 9 = -3x + 20

Add 3x to both sides.

8x - 9 = 20

Add 9 to both sides.

8x = 29

Divide both sides by 28 to get:

x = 29/8.